I think this is right for both Ancelotti and Everton. Ancelotti is not a coach who has neither the energy nor the creativity for the job that needs to be done at Everton.
On the other hand, he fits perfectly in Real Madrid. A club that already has a good structure, and which has solid competence at all levels.
In addition, they are struggling financially, and have to make some cuts, and then the president needs a manager who accepts this without making a fuss about it. They will almost regardless of who is the manager qualify for the CL.
Ancelotti is also a world-renowned manager, and in that sense also appeals to the commercial market. However, I think he will soon be without a job again, as soon as Real Madrid has stabilized the economy.